The present invention relates to a method for monitoring gas stunning of birds, where groups of birds are conveyed into and out of a stunning zone, and where the concentration of the stunning gas in the stunning zone is measured and adjusted for optimal stunning, and to a monitoring system.
The applicant's prior patent application EP1405564A1 discloses a gas stunning system intended for poultry, where the stunning is optimized in respect of capacity, the size and number of birds in each group and the physical condition of the birds, which again depends on factors such as temperature, transport time and waiting time in the slaughterhouse. This optimization is achieved by shortening or prolonging the conveying time and/or the conveying route through the stunning zone if the birds are not properly stunned when coming out of the stunning zone.
Introducing the system known from EP1405564A1 has made the slaughtering process more efficient, since the number of birds which are killed prematurely due to excessive stunning has been minimized, and has also contributed considerably to the welfare of the birds.